What is Decode Pixel Format?

TouchDesigner Documentation
1

Hi,

I’m trying to get a better understanding on what’s happening under the hood with the Decode Pixel Format (Fastest/Best) and more specifically with Apple ProRes 422HQ decoding.

In fastest I get a lot of banding artifacts that are invisible in other applications (Resolve for instance) and in Best they disappear. Is there some sort of dithering happening after decoding ? How does that impact performance ? Does-it have something to do with the bitdepth ? Does it have the same behavior with all codec ?

Best,

Mehdi

NEOSET

2

‘Best’ may pick a higher bit depth for the decode destination and what pixel format the texture in the TOP will hold the data. It doesn’t affect the decompression algorithm itself, just where the data ends up.

So ‘Fastest’ it ends up being faster for your overall network (since all downstream nodes are at a lower bit depth), and also lower GPU memory consumption.

3

Hey @malcolm this would be good to add to the docs as I can’t find a mention of it anywhere in documentation.

4

yep thanks, that’s updated now

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